Systems and Methods for Detecting and Rejecting Defective Absorbent Articles from A Converting Line

ABSTRACT

The present disclosure relates to systems and processes for detecting and rejecting defective absorbent articles from a converting line. In particular, the systems and methods may utilize feedback from technologies, such as vision systems, sensors, remote input and output stations, and controllers with synchronized embedded clocks to accurately correlate inspection results and measurements from an absorbent article converting process. As such, the systems and methods may accurately apply the use of precision clock synchronization for both instrumentation and control system devices on a non-deterministic communications network. In turn, the clock synchronized control and instrumentation network may be used to control a reject system on converters of absorbent articles. In some embodiments, the controller will reject only defective absorbent articles without the need to reject non-defective absorbent articles.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.12/476,553, filed Jun. 2, 2009, which is hereby incorporated byreference.

FIELD OF THE INVENTION

The present disclosure relates to systems and methods for manufacturingdisposable absorbent articles, and more particularly, systems andmethods for detecting and rejecting defective absorbent articles from aconverting line.

BACKGROUND OF THE INVENTION

Along an assembly line, diapers and various types of other absorbentarticles may be assembled by adding components to and otherwisemodifying an advancing, continuous web of material. For example, in someprocesses, advancing webs of material are combined with other advancingwebs of material. In other examples, individual components created fromadvancing webs of material are combined with advancing webs of material,which in turn, are then combined with other advancing webs of material.Webs of material and component parts used to manufacture diapers mayinclude: backsheets, topsheets, absorbent cores, front and/or back ears,fastener components, and various types of elastic webs and componentssuch as leg elastics, barrier leg cuff elastics, and waist elastics.Once the desired component parts are assembled, the advancing web(s) andcomponent parts are subjected to a final knife cut to separate theweb(s) into discrete diapers or other absorbent articles. The discretediapers or absorbent articles may also then be folded and packaged.

For quality control purposes, absorbent article converting lines mayutilize various types of sensor technology to detect various types ofdefects in the webs and discrete components added to the webs along theconverting line as absorbent articles are constructed. Example sensortechnology may include vision systems, photoelectric sensors, proximitysensors, laser or sonic distance detectors, and the like. Sensor datamay be communicated to a controller in various ways. In turn, thecontroller may be programmed to receive sensor data and reject or culldefective diapers after the final knife cut at the end of the convertingline.

However, the controller may not be able to track the exact locations ofdefects in the web and corresponding diapers with a very large degree ofaccuracy due to slow sensor and control loop times. For example, thesensor and control technologies may work asynchronously of each other,thus creating control system accuracy challenges, which may beexacerbated at the high speed production rates of some absorbent articleprocesses. For example, if data from a sensor is received by acontroller after a processing cycle has begun, the data will not beevaluated in the controller until after the next input cycle has beenreached. As such, a window in time is created during which an event maybe sensed but not acted upon in the controller. To compensate, thecontroller may be programmed to assume that the event happened atanytime within the previous processing cycle. Thus, in order to accountfor the controller's poor ability to track a defect, it may be necessaryto reject a relatively large number large number diapers to the frontand the rear of a detected defect location in order to provide a highdegree of confidence that the actual defective absorbent article isbeing rejected. As a result, a large number of non-defective articlesmay be rejected when attempting to reject defective articles. Inaddition, compensating for the aforementioned time delays may be furthercomplicated when the communication and processing cycles areasynchronous and variable, which prevents deterministic calculation ofthe delay between sensor detection of an event and the availability ofthe data to be evaluated by the processor.

SUMMARY OF THE INVENTION

The present disclosure relates to systems and processes for detectingand rejecting defective absorbent articles from a converting line. Inparticular, the systems and methods may utilize feedback fromtechnologies, such as vision systems, sensors, remote input and outputstations, and controllers with synchronized embedded clocks toaccurately correlate inspection results and measurements from anabsorbent article converting process. As such, the systems and methodsmay accurately apply the use of precision clock synchronization for bothinstrumentation and control system devices on a non-deterministiccommunications network. In turn, the clock synchronized control andinstrumentation network may be used to control a reject system onconverters of absorbent articles. In some embodiments, the controllerwill reject only defective absorbent articles without the need to rejectnon-defective absorbent articles.

In one form, a method for rejecting defective absorbent products from aweb converting manufacturing process includes the steps of: providing acommunication network; connecting a sensor with the communicationnetwork, the sensor including a sensor clock; connecting a controllerwith the communication network, the controller including a controllerclock; synchronizing the sensor clock with the controller clock suchthat the reported time of the controller clock and the sensor clock canbe correlated; advancing a substrate in a machine direction through aconverting process at a first speed; virtually segmenting the substrateinto a plurality of virtual products along the machine direction;virtually dividing the virtual products into a plurality of virtualsegments along the machine direction; sequentially adding componentparts to the substrate; inspecting the substrate and component partswith the sensor; communicating inspection parameters from the sensor tothe communication network; assigning a timestamp to each inspectionparameter, each timestamp based on the sensor clock; receiving theinspection parameters and corresponding timestamps from thecommunication network into the controller; correlating each inspectionparameter with one virtual segment based on the timestamp of theinspection parameter and the first speed of the substrate; identifyingdefects in virtual segments based on the inspection parameters; cuttingthe substrate with component parts added thereto into discrete absorbentarticles; rejecting absorbent articles that correspond with virtualproducts having virtual segments with identified defects; and packagingabsorbent articles that correspond with virtual products having virtualsegments with no identified defects.

In another form, a method for rejecting defective absorbent productsfrom a web converting manufacturing process includes the steps of:providing a communication network; connecting a sensor to a remote I/Ostation and connecting the remote I/O station to the network, the remoteI/O station including a sensor clock; connecting a controller with thecommunication network, the controller including a controller clock;synchronizing the sensor clock with the controller clock such that thereported time of the controller clock and the sensor clock can becorrelated; advancing a substrate in a machine direction through aconverting process at a first speed; virtually segmenting the substrateinto a plurality of virtual products along the machine direction;virtually dividing the virtual products into a plurality of virtualsegments along the machine direction; sequentially adding componentparts to the substrate; inspecting the substrate and component partswith the sensor; communicating inspection parameters from the sensor tothe communication network; assigning a timestamp to each inspectionparameter, each timestamp based on the sensor clock; receiving theinspection parameters and corresponding timestamps from thecommunication network into the controller; correlating each inspectionparameter with one virtual segment based on the timestamp of theinspection parameter and the first speed of the substrate; identifyingdefects in virtual segments based on the inspection parameters; cuttingthe substrate with component parts added thereto into discrete absorbentarticles; rejecting absorbent articles that correspond with virtualproducts having virtual segments with identified defects; and packagingabsorbent articles that correspond with virtual products having virtualsegments with no identified defects.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of an absorbent article convertingline and reject system.

FIG. 2 is a top view of an advancing substrate showing virtual productsand virtual segments.

FIG. 3A is a schematic side view of converting line, substrate, andcomponents.

FIG. 3B is a top view of the substrates and components that correspondswith FIG. 3A.

FIG. 4A is a schematic side view of converting line, substrate, andcomponents.

FIG. 4B is a top view of the substrates and components that correspondswith FIG. 4B.

FIG. 5A is a schematic side view of converting line, substrate, andcomponents.

FIG. 5B is a top view of the substrates and components that correspondswith FIG. 5A.

FIG. 6A is a schematic side view of converting line, substrate, andcomponents.

FIG. 6B is a top view of the substrates and components that correspondswith FIG. 6A.

FIG. 7A is a schematic side view of converting line, substrate, andcomponents.

FIG. 7B is a top view of the substrates and components that correspondswith FIG. 7A.

FIG. 8 is a top plan view of a disposable absorbent article that mayinclude one or more substrates and/or components monitored andconstructed in accordance with the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

The following term explanations may be useful in understanding thepresent disclosure: “Absorbent article” is used herein to refer toconsumer products whose primary function is to absorb and retain soilsand wastes. “Diaper” is used herein to refer to an absorbent articlegenerally worn by infants and incontinent persons about the lower torso.The term “disposable” is used herein to describe absorbent articleswhich generally are not intended to be laundered or otherwise restoredor reused as an absorbent article (e.g., they are intended to bediscarded after a single use and may also be configured to be recycled,composted or otherwise disposed of in an environmentally compatiblemanner).

The term “disposed” is used herein to mean that an element(s) is formed(joined and positioned) in a particular place or position as amacro-unitary structure with other elements or as a separate elementjoined to another element.

As used herein, the term “joined” encompasses configurations whereby anelement is directly secured to another element by affixing the elementdirectly to the other element, and configurations whereby an element isindirectly secured to another element by affixing the element tointermediate member(s) which in turn are affixed to the other element.

The term “substrate” is used herein to describe a material which isprimarily two-dimensional (i.e. in an XY plane) and whose thickness (ina Z direction) is relatively small (i.e. 1/10 or less) in comparison toits length (in an X direction) and width (in a Y direction).Non-limiting examples of substrates include a layer or layers or fibrousmaterials, films and foils such as plastic films or metallic foils thatmay be used alone or laminated to one or more web, layer, film and/orfoil. As such, a web is a substrate.

The term “nonwoven” refers herein to a material made from continuous(long) filaments (fibers) and/or discontinuous (short) filaments(fibers) by processes such as spunbonding, meltblowing, and the like.Nonwovens do not have a woven or knitted filament pattern.

The term “machine direction” (MD) is used herein to refer to thedirection of material flow through a process. The term “cross direction”(CD) is used herein to refer to a direction that is generallyperpendicular to the machine direction.

The present disclosure relates to systems and processes for detectingand rejecting defective absorbent articles from a converting line. Inparticular, the systems and methods herein focus on creating a moreaccurate reject system with improved set-up, defect detection, defecttracking, and validation algorithms. For example, the systems andmethods may utilize feedback from technologies, such as vision systems,sensors, remote input and output stations, and controllers withsynchronized embedded clocks to accurately correlate inspection resultsand measurements from an absorbent article converting process. As such,the systems and methods may accurately apply the use of precision clocksynchronization for both instrumentation and control system devices on anon-deterministic communications network, such as for example, anEthernetIP network. In turn, the clock synchronized control andinstrumentation network may be used to control a reject system onconverters of absorbent articles. Thus, the controller may be programmedto track defects in substrates and components along the converting linewithout having to account for undeterminable delays. In someembodiments, the controller will reject only defective absorbentarticles without the need to reject non-defective absorbent articles.

Although the present disclosure is provided in the context ofmanufacturing absorbent articles, and diapers in particular, it is to beappreciated that the systems and methods disclosed herein may be appliedto the manufacture of various types of articles and products involvingthe monitoring of various different types of substrates and/orcomponents. Examples of other products include absorbent articles forinanimate surfaces such as consumer products whose primary function isto absorb and retain soils and wastes that may be solid or liquid andwhich are removed from inanimate surfaces such as floors, objects,furniture and the like. Non-limiting examples of absorbent articles forinanimate surfaces include dusting sheets such as the SWIFFER cleaningsheets, pre-moistened wipes or pads such as the SWIFFER WETpre-moistened cloths, paper towels such as the BOUNTY paper towels,dryer sheets such as the BOUNCE dryer sheets and dry-cleaning clothessuch as the DRYEL cleaning clothes all sold by The Procter & GambleCompany. Additional examples of products include absorbent articles foranimate surfaces whose primary function is to absorb and contain bodyexudates and, more specifically, devices which are placed against or inproximity to the body of the user to absorb and contain the variousexudates discharged from the body. Non-limiting examples of incontinentabsorbent articles include diapers such as PAMPERS diapers, training andpull-on pants such as PAMPERS FEEL'N LEARN and EASY UPS, adultincontinence briefs and undergarments such as ATTENDS adult incontinencegarments, feminine hygiene garments such as panty liners, absorbentinserts, and the like such as ALWAYS and TAMPAX, toilet paper such asCHARMIN toilet paper, tissue paper such as PUFFS tissue paper, facialwipes or clothes such as OLAY DAILY FACIAL wipes or clothes, toilettraining wipes such as KANDOO pre-moistened wipes, all sold by TheProcter & Gamble Company. Still other examples of products includepackaging components and substrates and/or containers for laundrydetergent and coffee, which may be produced in pellets or pouches andmay be manufactured in a converting or web process or even discreetproducts produced at high speed such as high-speed bottling lines orcosmetics. Still other examples of products include a web substratecontaining labels to be placed on bottles and/or containers for laundrydetergent (such as Tide, Gain, etc.), fabric enhancers (such asFebreeze, Downy, etc.), hair and beauty care products (such as Head &Shoulders, Old Spice deodorant/antiperspirant, Herbal Essence, Pantene,etc.), and cleaning products (such as Mr. Clean, Cascade, Dawn, Ivory,etc.). Further, it is to be appreciated that although the presentdisclosure often refers to monitoring or viewing substrates and/or webs,it is to be appreciated that the inspection systems discussed herein canbe used to monitor and/or view combinations of webs and individualcomponents as well as parts added as a continuous web of material andparts added as a discontinuous web of material.

FIG. 1 shows a schematic representation of an absorbent articleconverting process including a converting line or machine 100 configuredto manufacture diapers. It is to be appreciated that the systems andmethods disclosed herein are applicable to work with various types ofconverting processes and/or machines. As shown in FIG. 1, the convertingline 100 may include one or more motors 102 that drive transportsystems, such as a nip roll 104, to move diaper substrates and componentmaterials through the manufacturing process. For example, FIG. 1 shows abase substrate 106 and two auxiliary substrates and/or components 108 ofmaterial used to construct portions of the diapers. The substrates maybe provided as rolls and fed into the converting line 100. It is to beappreciated that material of the auxiliary substrates may be supplied invarious ways. For example, FIG. 1 shows a first auxiliary substrate 110in the form of a continuous substrate 112, and a second auxiliarysubstrate 114 in the form of individual components 116. It is to beappreciated that the auxiliary substrates 110 may be transferred to thebase substrate through various types of transfer mechanisms. Forexample, the individual components 116 are shown as being transferred tothe base substrate via a transfer mechanism 118 in the form of a servopatch placer mechanism 120, such as disclosed in U.S. Pat. Nos.6,450,321; 6,705,453; 6,811,019; and 6,814,217. It is also to beappreciated that the various substrates can be used to construct variouscomponents of the absorbent articles, such as backsheets, topsheets, andabsorbent cores. Exemplary descriptions of absorbent article componentsare provided below with reference to FIG. 8. Referring back to FIG. 1,as the base substrate 106 advances through the converting line 100, thebase substrate 106 is combined with the auxiliary substrates 108 and/ordiscrete components 116 to create a continuous length of absorbentarticles 122. At a downstream portion of the converting process 100, thecontinuous length of absorbent articles 122 is subjected to a finalknife 124 and cut to create separate and discrete absorbent articles 126in the form of diapers 128. As discussed in more detail below, defectivearticles 130 may be subject to a rejection system 132 and removed fromthe process. For example, FIG. 1 shows defective diapers being channeledto a reject bin 136. Diapers 134 that are not deemed to be defective maybe subject to further processing steps, such as folding and packaging.For example, FIG. 1 shows non-defective diapers advancing from the finalknife 124 to a folding mechanism 138.

It is to be appreciated that various types reject systems 132 may beused to physically remove defective diapers 130. For example, in someembodiments, a pneumatic system may be used to remove defectiveabsorbent articles from the assembly line. More particularly, afterapplication of the final knife and before being folded by a foldingmechanism, defective articles 130 are removed from the assembly line bya blast of compressed air discharged from the pneumatic system. In otherembodiments, defective articles 130 may be allowed to advance from thefinal knife 124, partially through a folding mechanism, and into areject bin. Such a system, described for example in U.S. PatentPublication No. US20080223537A1, may stop or slow the motion of tuckerblades on the folding mechanism such that a rejected article will passthrough a portion of the folding mechanism without being folded and fallinto a reject bin. After the defective articles have passed through thefolding mechanism, motion of the tucker blades is resumed, allowing thetucker blades to engage non-defective articles and causing thenon-defective articles to be folded and channeled toward a packagingprocess downstream of the folding mechanism.

As shown in FIG. 1 and as described in more detail below, varioussensors 140 and other devices may be arranged adjacent the convertingline 100 may communicate with a controller 142. Based on suchcommunications, the controller 142 may monitor and affect variousoperations on the converting line 100. As discussed in more detailbelow, the controller may send reject commands 1002 to the reject systembased on communications with the sensors 140. In the systems and methodsdescribed herein, the controller 142 includes a computer system. Thecomputer system may, for example, include one or more types ofprogrammable logic controller (PLC) and/or personal computer (PC)running software and adapted to communicate on an EthernetIP network.Some embodiments may utilize industrial programmable controllers such asthe Siemens S7 series, Rockwell ControlLogix, SLC or PLC 5 series, orMitsubishi Q series. The aforementioned embodiments may use a personalcomputer or server running a control algorithm such as RockwellSoftLogix or National Instruments Labview or may be any other devicecapable of receiving inputs from sensors, performing calculations basedon such inputs and generating control actions through servomotorcontrols, electrical actuators or electro-pneumatic, electrohydraulic,and other actuators.

As the substrates and components travel in the machine direction MDthrough the converting line, the controller tracks the advancement ofthe substrates and components. In some embodiments such as shown in FIG.1, the controller 142 may track the advancement with counts generated bya machine axis 144 that correspond with machine direction positions onsubstrates and components while advancing though the converting line100. In some configurations, the machine axis 144 may be configured asan actual motor 146 that provides count signals 1004 to the controller142. The controller 100 may utilize rotational speed, time, and/or countdata from the machine axis 144 that correspond with the machinedirection speed and travel of the substrates and components through theconverting line 100.

It is to be appreciated that instead of or in addition to utilizingfeedback from a physical machine axis as discussed above, the rotationalmotion of the machine axis 144 may be simulated by software in thecontroller. For example, in FIG. 1, the controller 100 can utilizecounts generated by a virtual machine axis 148 in the controllersoftware. More particularly, the virtual machine axis 148 may beprogrammed to imitate a motor that generates counts as the motorrotates. As such, it is to be appreciated that the machine axis 144referred to herein may be either a virtual axis existing in software ora physical axis corresponding with the rotational motion of a motor orother equipment.

As discussed above, the machine axis 144 may be configured to correlatethe linear motion of the substrates and components in the machinedirection MD through the converting line 100 with counts correspondingwith rotation of the machine axis 144. In some embodiments, one completerotation of the machine axis 144 and associated count data correspondwith one pitch length of an absorbent article 126. In some embodiments,the pitch lengths of the absorbent articles are the machine directionlongitudinal lengths of the individual absorbent articles beingproduced. FIG. 8 shows an example of a longitudinal pitch length PL of adiaper. As such, the controller 142 may use counts generated from themachine axis 144 to virtually divide the substrates and components intovirtual products 150. As shown in FIG. 2, the virtual products 150 mayhave machine direction lengths 151 that correspond with the pitchlengths of products being produced. For example, FIG. 2 shows a top sideview of the base substrate 106 divided into virtual products 150 alongthe machine direction MD by the controller 142. Count signalscorresponding with rotation of the machine axis that correspond withless than a complete rotation can also be used by the controller divideeach virtual product 150 into virtual segments 152, such as shown inFIG. 2. As discussed in more detail below, the substrate speed andestimated clock inaccuracies can be used to determine the length of theeach virtual segment in the machine direction MD, and in turn, thenumber of virtual segments in each virtual product. For example, FIG. 2shows one virtual product 150 divided into twenty virtual segments 152.As discussed in more detail below, the controller 142 can also utilizesignals from the inspection sensor 140 that corresponds with thedetection of defects in virtual products and segments to correlate thelocations of defects within defective products 130.

As previously mentioned, the systems and methods herein utilize varioustypes of sensors to monitor the substrates and components travelingthrough the converting line. As shown in FIG. 1, various types ofinspection sensors 140 may be used to detect defects in the substrates106, 108, 110 and/or components 116. In particular, the inspectionsensors 140 may detect defects within substrates and/or componentsthemselves, such as for example, damage, holes, tears, dirt, and thelike, and may also detect defective assemblies and/or combinations ofthe substrates and components, such as for example, missing and/ormisplaced ears, landing zones, fasteners, and the like. As such,inspection sensors may be configured to detect the presence or absenceof substrates and/or components, and may be configured to detect therelative placement of substrates and/or components. As discussed in moredetail below, based on the detections of the inspection sensors 140,feedback signals from the inspection sensors in the form of inspectionparameters 1000 are communicated to the controller.

It is to be appreciated that various different types of inspectionsensors 140 may be used to monitor substrates and various componentswhile advancing through the converting line 100. For example, inspectionsensors 140 may be configured as photo-optic sensors that receive eitherreflected or transmitted light and serve to determine the presence orabsence of a specific material; metal-proximity sensors that useelectromagnetic to determine the presence or absence of a ferromagneticmaterial; or capacitive or other proximity sensors using any of a numberof varied technologies to determine the presence or absence materials.Inspection sensors 140 may also be configured as vision systems andother sub-processing devices to perform detection and, in some cases,logic to more accurately determine the status of an inspected product.Particular examples of such inspections sensors 140 may include CognexInsight, DVT Legend or Keyence smart cameras, component vision systemssuch as National Instruments PXI or PC based vision system such asCognex VisionPro or any other vision system software which can run on aPC platform.

It should also be appreciated that inspection parameters 1000 may beprovided from inspection sensors 140 in various forms. In oneembodiment, inspection parameters 1000 may be in the form of “results,”such as for example, provided from a sensor state change resulting in abinary input corresponding with the detected presence or absence of adefect, such as for example, the presence or absence of componentsand/or substrates. For example, inspection parameters 1000 may indicatethe presence or absence of an ear, landing zone, and/or printed graphicson a product. In another example, an inspection parameter 1000 mayindicate the presence or absence of a tear, hole, splice tape, and/orcontaminants in a substrate and/or component. In another embodiment,inspection parameters 1000 may be provided in the form of measurementsand/or numerical indications of detected positions of components and/orsubstrates; numerical indications of the positions of components and/orsubstrates relative to other components and/or substrate; and/ornumerical indications of the positions of components and/or substratesrelative to another physical or virtual reference. For example,inspection parameters 1000 may indicate the relative position of onefeature, such as a back ear fastener, with respect to a back earsubstrate or the measured width of a main chassis compared to thedesired width. In other embodiments, inspection parameters 1000 may bein the form of images transferred via a standard protocol such as ftp(File Transfer Protocol), DDE (Dynamic Data Exchange), or OPC (ObjectLinking and Embedding for Process Control), which are stored in adatabase or stored in a specified directory on an image server for thepurpose of either operator visualization, offline image processing orclaim support.

As shown in FIG. 1, the inspection sensors 140 are connected with thecontroller 142 through a communication network 154, which allows theinspection sensors 140 to communicate inspection parameters 1000 to thecontroller 142. As discussed in more detail below, devices thatcommunicate on the network each include precision clocks that aresynchronized to a master clock within some specified accuracy. As shownin FIG. 1, the inspection sensors 140 and the controller 142 may beconnected directly with the communication network 154. As such, eachsensor or other field device connected directly with the communicationnetwork may include a clock. Inspection sensors 140 that include a clockand that may be connected directly with the communication network 154may include, for example, vision systems such as National InstrumentsCVS or any PC-based vision system such as Cognex VisionPro. Such sensorsmay also include other controllers that may be configured as peers tothe controller or may be configured as subordinate to the controller.

In some embodiments, the inspection sensors 140 may be indirectlyconnected with the communication network 154. For example, theinspections sensors 140 may be connected with the communication network154 through a remote input and output (I/O) station 156. When utilizingremote I/O stations 156, the inspection sensors 140 may be hardwired tothe remote I/O stations, and in turn, the remote I/O stations areconnected with the communication network 154. As such, the each remoteI/O station 156 may include a precision clock. Example remote I/Ostations 156 or other IEEE-1588 based instruments that can be utilizedwith systems and methods herein include, for example a NationalInstruments PCI-1588 Interface (IEEE 1588 Precision Time ProtocolSynchronization Interface) that synchronizes PXI systems, I/O modulesand instrumentation over Ethernet/IP or a Beckhoff Automation EtherCatand XFC technology (eXtreme Fast Control Technology).

As previously mentioned, each device, such as the inspection sensors140, remote I/O stations 156, and the controller 142, connected with thecommunication network 154 includes a clock, and each clock issynchronized to a master clock. In one configuration, the controller 142includes the master clock, and all other clocks of devices connectedwith the communication network are referenced to the controller masterclock. In such a configuration, the remote I/O stations and inspectionsensors each include a clock that is synchronized to the controllermaster clock. Inspection parameters provided by the inspection sensors140 and communicated to the communication network 154 are time-stampedwith the time from the clocks on the corresponding sensors and remoteI/O stations. In turn, the inspection parameters and correspondingtimestamp data is sent to the controller over the communication network154. Thus, the controller can be programmed to evaluate the inspectionparameter based on the actual time the inspection parameter was providedby the inspection sensor. Therefore, ambiguity as to when detectionswere actually made by an inspection sensor is relatively small.

As previously mentioned, all clocks that are used to determine andreport timestamps may be synchronized together. Clock synchronizationallows the reported time from one device on the communication network154 to be utilized by another device on the communication network. Whenthe clocks are synchronized, ambiguity as to when an inspectionparameter was actually provided by the inspection sensor 140 is affectedonly by the accuracy of the clocks with respect to each other. Theclocks of the devices on the communication network may be synchronizedin various ways depending on the type of communication network 154 used.

In one embodiment, the communication network 154 is configured as anon-deterministic communication network, such as for example, Ethernetor Ethernet IP (industrial protocol) communication network. When usingan Ethernet IP communication network, the clocks of each device may besynchronized using the IEEE1588 precision time protocol, described inIEEE1588 Standard, “Precision Clock Synchronization Protocol forNetworked Measurement and Control Systems” and also described inRockwell Automation publication number 1756-WPO05A-EN-E, publishedJanuary 2009, and entitled “An Application of IEEE 1588 to IndustrialAutomation.” As mentioned above, timestamps associated with inspectionparameters from any inspection sensor may be referenced to the masterclock, which allows the relative time as to when the inspectionparameters were provided to be accurately calculated. In oneconfiguration, the controller includes the master clock, the controllermaster clock, and all other clocks of devices connected with thecommunication network, the sensor clocks, are referenced to thecontroller master clock. As a result, the time as to when an inspectionparameter was provided from an inspection sensor can be can be reportedto the controller within the accuracy of an IEEE1588 compliant clock. Insome embodiments, reported timestamps may be accurate to within 0.1milliseconds of the controller master clock. In another configuration,another device, such as an Ethernet switch or router is the local masterclock. In this case, both the controller clock and the sensor clockfollow the local master clock. The identity of the local master isunimportant since all clocks in the system are synchronized to the localmaster within the IEEE1588 PTP standard,

With reference to the above description and figures, the methods andsystems herein utilize a controller 142 and one or more inspectionsensors 140 connected with a communication network 154. Each sensor 140,and remote I/O device 156, if used, have clocks that are synchronizedwith the master controller clock in the controller. The controller 142tracks the movement of the substrates and components traveling in themachine direction of the converting line 100. More particularly,controller 142 utilizes feedback from the machine axis 144 to virtuallydivide the substrates and components into virtual products 150 along themachine direction, track the movement of virtual products 150 in themachine direction, and correlate the virtual products 150 to actualindividual products 126 produced after the final knife 124 cut. Inaddition, the controller 142 utilizes feedback from the machine axis 144to virtually divide the virtual products 150 into virtual segments 152along the machine direction. The inspection sensors 140 provideinspection parameters 1000 to the controller 142 via the communicationnetwork 154. As discussed above, the inspection parameters 1000 can beconfigured to indicate various types of defects in the substrates and/orcomponents. The sensors 140 provide inspection parameters 1000 to thecommunication network along with associated timestamp from the sensorclocks. The controller receives the inspection parameters 1000 andassociated timestamps from the communication network 154 and correlatesthe inspection parameters with the corresponding virtual products 150and/or virtual segment 152 moving along the converting line 100. Once avirtual product 150 is deemed defective, the controller 142 willcorrelate the defective virtual product 150 with a defective individualproduct 130, and the controller will send a reject command 1002 therejection system 132 to reject or cull the defective individual product130.

To provide additional context to the above discussion, the followingprovides a specific description of one example implementation of thereject systems and processes herein. FIGS. 3A-7B show an example of anabsorbent article converting line 100 as substrates and componentstravel along the machine direction MD to a final knife cut 124 and afolding and/or packing system 138. In particular, FIGS. 3A, 4A, 5A, 6A,and 7A show schematic side views of the converting line 100, substrates106, 108 and components 116, and FIGS. 3B, 4B, 5B, 6B, and 7B show a topview of the substrates 106 and components 116 that correspond with FIGS.3A, 4A, 5A, 6A, and 7A, respectively. For the purposes of the discussionrelating to FIGS. 3A-7B, the converting line 100 is described in thecontext of a diaper converting line. In particular, a base substrate 106is shown to enter and advance in the machine direction MD through theconverting line 100. Material from an auxiliary substrate 108 is cutinto individual components 116, transferred and bonded to the basesubstrate 106 to form features 158 on the base substrate 106, such asfor example, front ears on a diaper. FIGS. 3A, 4A, 5A, 6A, and 7A alsoshow an inspection sensor 140, controller 142, machine axis 144, padreject system 132, and folding system 138 associated with the convertingline 100. In accordance with the above description, the machine axis 144is shown schematically in the form of a virtual axis 148 provides basesubstrate position and speed signals to the controller 142. In turn, thecontroller 142 divides the base substrate into virtual products 150along the machine direction MD. For the purposes of the presentdescription, FIGS. 3A-7B show only three virtual products 150. Also inaccordance with the above discussion, the inspection sensor 140 isconnected with a remote I/O station 156. In turn, the remote I/O station156 and controller 142 are connected with a communication network 154,in the form of an Ethernet IP network. It is to be appreciated that themore than inspection sensor 140 may be used and that some or allinspection sensors may be connected directly with the communicationnetwork 154 without using a remove I/O station. The remote I/O stationincludes a clock 1006, referred to herein as a sensor clock 1008providing a time, Ts, and the controller includes a clock 1006, referredto herein as the master control clock 1010 providing a time, Tc. Thesensor clock 1008 is synchronized with the master control clock 1010,such that Ts is set to equal Tc.

As shown in FIGS. 3A-7A, the lengths 151 of the virtual products 150 inthe machine direction correspond with the pitch lengths PL of products126 being produced. For the purposes of discussion, it is assumed thatvirtual product pitch length 151 is 600 mm and the base substrate 106travels in the machine direction at a speed of 300 meters per minute, or500 products per minute. In the present example, it is assumed that themachine axis 144 rotates such that one complete one rotation correspondswith a one pitch length 151 advancement of the base substrate 106 in themachine direction, and as such, one complete rotation of the machineaxis 144 occurs every 120 milliseconds. Upon each revolution of themachine axis 144, a shift register in the controller 142 is incrementedby one virtual product 150. For example, FIGS. 3A and 3B show the basesubstrate 106 advancing in the machine direction MD past a referencepoint 160 in the converting line 100. At the reference point 160, afirst virtual product identified as 150 a is present at the referencepoint at a first time, t₁. At a second time, t₂, 120 milliseconds aftert₁, a second virtual product identified as 150 b is present at the samereference point, meanwhile the first virtual product 150 a hasprogressed one pitch or 600 mm downstream in the machine direction.Continuing on, at a third time, t₃, 120 milliseconds after t₂, a thirdvirtual product identified as 150 c is present at the same referencepoint 160, meanwhile the first and second virtual products 150 a, 150 bhave progressed one pitch or 600 mm downstream in the machine direction.The aforementioned increments continue as the base substrate 106 movesthrough the converting line 100. FIGS. 3A and 3B also show the additionof front ears 158 to the first virtual product 150 a.

FIGS. 4A and 4B show the advancement of the base substrate 106 in themachine direction past the inspection sensor 140. As discussed above,the inspection sensor 140 can be configured to perform various detectionoperations. In one example, the inspection sensor 140 detects thepresence or absence of the front ears 158 on the virtual products 150passing thereby. As such, the inspection sensor 140 provides aninspection parameter 1000 to the communication network via the remoteI/O station, wherein the inspection parameter 1000 corresponds with thesensed presence or absence of the front ears 158. In accordance with theabove discussion, the inspection parameter includes a correspondingtimestamp from the sensor clock 1008. When the position of theinspection sensor 140 along the converting line is known by thecontroller 142, the controller 142 can correlate the inspectionparameters 1000 provided by the inspection sensor 140 with thecorresponding virtual products 150 based on the timestamps of theinspection parameters 1000.

FIGS. 4A and 4B show the continued advancement from FIGS. 3A and 3B ofthe base substrate in the machine direction, and in particular,advancement of the first virtual product past the inspection sensor 140.As shown in FIG. 4B, two front ears 158 are present on the first virtualproduct 150 a. FIG. 4A shows a first inspection parameter, IS1, having acorresponding timestamp, Ts1, being communicated to the communicationnetwork 154. IS1 may be configured to provide an indication that bothfront ears 158 are present on the first virtual product 150 a.Simultaneously, the time reported by master controller clock 1010 isTc1. As discussed below, IS1 may not be immediately received by thecontroller 142.

Next, FIGS. 5A and 5B show the continued advancement from FIGS. 4A and4B of the base substrate 106 in the machine direction MD, and inparticular, advancement of the second virtual product 150 b past theinspection sensor 140. As shown in FIG. 5B, one of the front ears 158 ismissing from the second virtual product 150 b. FIG. 5A shows a secondinspection parameter, IS2, having a corresponding timestamp, Ts2, beingcommunicated to the communication network 154. IS2 provides anindication that one front ear 158 is missing from the second virtualproduct 150 b. Simultaneously, the time reported by master controllerclock 1010 is Tc2. Again, IS2 may not be immediately received by thecontroller 142 from the communication network 154.

Next, FIGS. 6A and 6B show the continued advancement from FIGS. 5A and5B of the base substrate 106 in the machine direction, and inparticular, advancement of the third virtual product 150 c past theinspection sensor 140. As shown in FIG. 6B, two front ears 158 arepresent on the third virtual product 150 c. FIG. 6A shows a thirdinspection parameter, IS3, having a corresponding timestamp, Ts3, beingcommunicated to the communication network 154. IS3 may be configured toprovide an indication that both front ears 158 are present on the thirdvirtual product 150 c. Simultaneously, the time reported by mastercontroller clock 1010 is Tc3. Again, IS3 may not be immediately receivedby the controller 142 from the communication network 154.

As previously mentioned, some amount of time may pass before thecontroller 142 receives the inspection parameters 1000 from thecommunication network 154. Such time delays may be the result of thenon-deterministic nature of the Ethernet IP network. There may also beadditional time before a controller analyzes the inspection parametersbased on the controller's program cycle or loop time. However,notwithstanding such time delays, once the controller receives andanalyzes inspection parameters, the controller can use the correspondingtimestamps of the inspection parameters to correlate the inspectionparameters 1000 with particular virtual products 150. For example, thecontroller may receive and analyze IS2 at some time after IS2 wasprovided to the communication network 154. However, along with IS2, thecontroller 142 will receive Ts2, which was provided by the sensor clock1010. Because the sensor clock 1008 is synchronized with the mastercontroller clock 1010, the controller 142 can correlate IS2 with thesecond virtual product 150 b. As discussed above, IS2 may be configuredto provide an indication that one front ear 158 is missing from thesecond virtual product. As such, the controller 142 may deem the secondvirtual product 150 b as being defective. In turn, the controller 142correlates the virtual products 150 a, 150 b, 150 c with individualproducts 126 a, 126 b, 126 c and may send a signal to the reject system132 to reject the individual diaper 130 b that corresponds with thesecond virtual product 150 b, such as shown in FIGS. 7A and 7B.

Because the inspection parameters 1000 have timestamps provided fromsensor clocks 1008 that are synchronized with the master controllerclock 1010, the controller 142 can correlate the inspection parameters1000 with actual physical locations on the substrates and/or componentsadvancing through the converting line 100 without having to account forvarious system time delays, such as time delays in the communicationnetwork and controller loop times. As such, the correlated location ofthe inspection parameters on the substrates and/or components may beaccurate to within the accuracy of the sensor clock with respect to themaster controller clock. For example, where the clock accuracy meets thesoftware implementation of IEE1588, the clocks may be assured to beaccurate within 0.1 milliseconds. In such a case, the position of aninspection parameter 1000, such as for IS2 in the example above, may beknown to within 0.5 mm in the machine direction MD on the base substrate106.

Expanding on the above discussion of the example provided in FIGS.3A-7B, it is to be appreciated that the controller 142 can utilized themachine axis 144 to further divide the virtual products 150 into virtualsegments 152, such as described above with reference to FIG. 2. As such,the controller 142 may correlate the inspection parameters 1000 withactual physical locations within the virtual products 150. In accordancewith the present disclosure, it is to be further appreciated that theinspection sensors 140 can be configured to provide various types ofinspection parameters 1000 that may be utilized by the controller invarious ways to execute the rejection of defective products 130. Forexample, as discussed above, the inspection parameter 1000 may beconfigured in the form of result that corresponds with the detectedpresence or absence of a component 116. In another example, theinspection parameter 1000 may be configured in the form of measurementor numerical values that correspond with the positions of substratesand/or components relative to each other or some other physical orvirtual reference point. In still another example, the inspectionparameter 1000 may be configured in the form of a result thatcorresponds to a detection of a feature signal from the inspectionsensor. Together with the associated timestamp of the received signal,the controller 142 can calculate the position of the feature detectionwithin the virtual product by calculating the virtual segment thatcorresponds with the received sensor detection at the correspondingsensor timestamp. In that way, the evaluation of a defect can beisolated to a certain position or segment of the product, allowing thecontroller to correlate the presence of a sensor's input with certainpositions within the product, but generating a defect result if the samedetection is made in another position within the product. For example,if a sensor is placed to detect the front ear of a diaper and thedetection occurs of the leading edge and the trailing edge of the frontear, the detection events, along with the sensor timestamps may be usedby the controller to allow the front ear at the front end of the diaper,but to generate a defect result if the front ear is placed in the middleof the diaper. As such, in some configurations, the controller may beconfigured to simply reject defective products based on defect signalsfrom the inspection sensors. In other examples, the controller may beconfigured to compare numerical values and/or measurements provided bythe inspection sensors to allowable limits in order to determine ifproducts are defective. In yet other examples, the controller mayanalyze images provided by the inspection sensors to determine ifproducts are defective.

As previously mentioned, the systems and methods herein may be used tomonitor various types of substrates and components during themanufacture of various different products. For the purposes of aspecific illustration, FIG. 8 shows one example of a disposableabsorbent article 750, such as described in U.S. Patent Publication No.US2008/0132865 A1, in the form of a diaper 752 that may be constructedfrom substrates and components monitored according to the systems andmethods disclosed herein. In particular, FIG. 8 is a plan view of oneembodiment of a diaper 752 including a chassis 754 shown in a flat,unfolded condition, with the portion of the diaper 752 that faces awearer oriented towards the viewer. A portion of the chassis structureis cut-away in FIG. 8 to more clearly show the construction of andvarious features that may be included in embodiments of the diaper.

As shown in FIG. 8, the diaper 752 includes a chassis 754 having a firstear 756, a second ear 758, a third ear 760, and a fourth ear 762. Toprovide a frame of reference for the present discussion, the chassis isshown with a longitudinal axis 764 and a lateral axis 766. The chassis754 is shown as having a first waist region 768, a second waist region770, and a crotch region 772 disposed intermediate the first and secondwaist regions. The periphery of the diaper is defined by a pair oflongitudinally extending side edges 774, 776; a first outer edge 778extending laterally adjacent the first waist region 768; and a secondouter edge 780 extending laterally adjacent the second waist region 770.As discussed above, the pitch length, PL, of the absorbent article 750may be defined by the distance between the first outer edge 778 and thesecond outer edge 780. As shown in FIG. 8, the chassis 754 includes aninner, body-facing surface 782, and an outer, garment-facing surface784. A portion of the chassis structure is cut-away in FIG. 8 to moreclearly show the construction of and various features that may beincluded in the diaper. As shown in FIG. 8, the chassis 754 of thediaper 752 may include an outer covering layer 786 including a topsheet788 and a backsheet 790. An absorbent core 792 may be disposed between aportion of the topsheet 788 and the backsheet 790. As discussed in moredetail below, any one or more of the regions may be stretchable and mayinclude an elastomeric material or laminate as described herein. Assuch, the diaper 752 may be configured to adapt to a specific wearer'sanatomy upon application and to maintain coordination with the wearer'sanatomy during wear.

As previously mentioned, the chassis 754 of the diaper 752 may includethe backsheet 790, shown for example, in FIG. 8. In some embodiments,the backsheet is configured to prevent exudates absorbed and containedwithin the chassis from soiling articles that may contact the diaper,such as bedsheets and undergarments. Some embodiments of the backsheetmay be fluid permeable, while other embodiments may be impervious toliquids (e.g., urine) and comprises a thin plastic film. Some backsheetfilms may include those manufactured by Tredegar Industries Inc. ofTerre Haute, Ind. and sold under the trade names X15306, X10962, andX10964. Other backsheet materials may include breathable materials thatpermit vapors to escape from the diaper while still preventing exudatesfrom passing through the backsheet. Exemplary breathable materials mayinclude materials such as woven webs, nonwoven webs, composite materialssuch as film-coated nonwoven webs, and microporous films. Suitablebreathable composite materials are described in greater detail in PCTApplication No. WO 95/16746, published on Jun. 22, 1995 in the name ofE. I. DuPont and U.S. Pat. No. 5,865,823, both of which are herebyincorporated by reference herein. Other breathable backsheets includingnonwoven webs and apertured formed films are described in U.S. Pat. Nos.5,571,096 and 6,573,423, which are all hereby incorporated by referenceherein.

The backsheet 790, or any portion thereof, may be stretchable in one ormore directions. In one embodiment, the backsheet may comprise astructural elastic-like film (“SELF”) web. Embodiments of SELF webs aremore completely described in U.S. Pat. Nos. 5,518,801; 5,723,087;5,691,035; 5,916,663; and 6,027,483, which are all hereby incorporatedby reference herein. In some embodiments, the backsheet may compriseelastomeric films, foams, strands, nonwovens, or combinations of theseor other suitable materials with nonwovens or synthetic films.Additional embodiments include backsheets that comprise a stretchnonwoven material; an elastomeric film in combination with an extensiblenonwoven; an elastomeric nonwoven in combination with an extensiblefilm; and/or combinations thereof. Details on such backsheet embodimentsare more completely described in U.S. Publication Nos. US2007/0287348A1;US2007/0287982A1; and US2007/0287983A1, which are all herebyincorporated by reference herein. The backsheet 790 may be joined withthe topsheet 788, the absorbent core 792, and/or other elements of thediaper 752 in various ways. For example, the backsheet may be connectedwith a uniform continuous layer of adhesive, a patterned layer ofadhesive, or an array of separate lines, spirals, or spots of adhesive.One embodiment utilizes an open pattern network of filaments of adhesiveas disclosed in U.S. Pat. No. 4,573,986, which is hereby incorporated byreference herein. Other embodiments utilize several lines of adhesivefilaments which are swirled into a spiral pattern, as is illustrated bythe apparatus and methods shown in U.S. Pat. Nos. 3,911,173; 4,785,996;and 4,842,666, which are all hereby incorporated by reference herein. Insome embodiments, the backsheet is connected with heat bonds, pressurebonds, ultrasonic bonds, dynamic mechanical bonds, or any other suitableattachment means or a combination thereof.

The topsheet 788 may be constructed to be compliant, soft feeling, andnon-irritating to the wearer's skin. Further, all or at least a portionof the topsheet 788 may be liquid pervious, permitting liquid to readilypenetrate therethrough. As such, the topsheet may be manufactured from awide range of materials, such as porous foams; reticulated foams;apertured nonwovens or plastic films; or woven or nonwoven webs ofnatural fibers (e.g., wood or cotton fibers), synthetic fibers (e.g.,polyester or polypropylene fibers), or a combination of natural andsynthetic fibers. One example of a topsheet including a web of staplelength polypropylene fibers is manufactured by Veratec, Inc., a Divisionof International Paper Company, of Walpole, Mass. under the designationP-8. Examples of formed film topsheets are described in U.S. Pat. Nos.3,929,135; 4,324,246; 4,342,314; 4,463,045; and 5,006,394, all of whichare hereby incorporated by reference herein. Other topsheets may be madein accordance with U.S. Pat. Nos. 4,609,518 and 4,629,643, both of whichare hereby incorporated by reference herein.

In some embodiments, the topsheet 788 is made of a hydrophobic materialor is treated to be hydrophobic in order to isolate the wearer's skinfrom liquids contained in the absorbent core. If the topsheet is made ofa hydrophobic material, at least the upper surface of the topsheet maybe treated to be hydrophilic so that liquids will transfer through thetopsheet more rapidly. The topsheet can be rendered hydrophilic bytreating it with a surfactant or by incorporating a surfactant into thetopsheet. A more detailed discussion of such a treatment andhydrophilicity is contained in U.S. Pat. Nos. 4,988,344 and 4,988,345,all of which are hereby incorporated by reference herein. A moredetailed discussion of some methods for incorporating surfactant in thetopsheet can be found in U.S. Statutory Invention Registration No.H1670, which was published on Jul. 1, 1997, in the names of Aziz et al.,all of which are hereby incorporated by reference herein. In someembodiments, the topsheet 788 may include an apertured web or film thatis hydrophobic. This may be accomplished eliminating the hydrophilizingtreatment step from the production process and/or applying a hydrophobictreatment to the topsheet, such as a polytetrafluoroethylene compoundlike SCOTCHGUARD or a hydrophobic lotion composition, as describedbelow. A more detailed discussion of various apertured topsheets can befound in U.S. Pat. Nos. 5,342,338; 5,941,864; 6,010,491; and 6,414,215,all of which are hereby incorporated by referenced herein.

The absorbent core 792 may include absorbent material that is generallycompressible, conformable, non-irritating to the wearer's skin, andcapable of absorbing and retaining liquids such as urine and other bodyexudates. The absorbent core 792 can also be manufactured in a widevariety of sizes and shapes (e.g., rectangular, hourglass, T-shaped,asymmetric, etc.). The absorbent core may also include a wide variety ofliquid-absorbent materials commonly used in disposable diapers and otherabsorbent articles. In one example, the absorbent core includescomminuted wood pulp, which is generally referred to as airfelt.Examples of other absorbent materials include creped cellulose wadding;meltblown polymers, including coform; chemically stiffened, modified orcross-linked cellulosic fibers; tissue, including tissue wraps andtissue laminates; absorbent foams; absorbent sponges; superabsorbentpolymers; absorbent gelling materials; or any other known absorbentmaterial or combinations of materials. Exemplary absorbent structuresare described in U.S. Pat. Nos. 4,610,678; 4,673,402; 4,834,735;4,888,231; 5,137,537; 5,147,345; 5,342,338; 5,260,345; 5,387,207; and5,650,222, all of which are hereby incorporated by reference herein.

The absorbent core 792 may also have a multiple layered construction. Amore detailed discussion of various types of multi-layered absorbentcores can be found in U.S. Pat. Nos. 5,669,894; 6,441,266; and5,562,646; European Patent No. EP0565606B1; U.S. Patent Publication No.2004/0162536A1; 2004/0167486A1; and PCT Publication No. WO 2006/015141,which are all hereby incorporated by reference herein. In someembodiments, the absorbent article includes an absorbent core that isstretchable. In such a configuration, the absorbent core may be adaptedto extend along with other materials of the chassis in longitudinaland/or lateral directions. The absorbent core can also be connected withthe other components of the chassis various ways. For example, thediaper may include a “floating core” configuration or a “bucket”configuration wherein the diaper includes an anchoring system that canbe configured to collect forces tending to move the article on thewearer. The absorbent article may also include an elastic waist feature702 shown in FIG. 8 in the form of a waist band 794 and may provideimproved fit and waste containment. The elastic waist feature 702 may beconfigured to elastically expand and contract to dynamically fit thewearer's waist. The elastic waist feature 702 can be incorporated intothe diaper in accordance with the methods discussed herein and mayextend at least longitudinally outwardly from the absorbent core 792 andgenerally form at least a portion of the first and/or second outer edges778, 780 of the diaper 752. In addition, the elastic waist feature mayextend laterally to include the ears. While the elastic waist feature702 or any constituent elements thereof may comprise one or moreseparate elements affixed to the diaper, the elastic waist feature maybe constructed as an extension of other elements of the diaper, such asthe backsheet 790, the topsheet 788, or both the backsheet and thetopsheet. In addition, the elastic waist feature 702 may be disposed onthe outer, garment-facing surface 784 of the chassis 754; the inner,body-facing surface 782; or between the inner and outer facing surfaces.The elastic waist feature 702 may be constructed in a number ofdifferent configurations including those described in U.S. PatentPublication Nos. 2007/0142806; 2007/0142798; and 2007/0287983, all ofwhich are hereby incorporated by reference herein.

Although the first and second ears 756, 158 as well as the third andfourth ears 760, 762 shown in FIG. 8 are illustrated as being integrallyformed with the chassis 754, it is to be appreciated that otherembodiments may include ears that are discrete elements connected withthe chassis. In some embodiments, the ears are configured to bestretchable. The ears may also include one or more fastener elementsadapted to releasably connect with each other and/or other fastenerelements on the chassis. A more detailed discussion of stretchable earscan be found in U.S. Pat. Nos. 4,857,067; 5,151,092; 5,674,216;6,677,258; 4,381,781; 5,580,411; and 6,004,306, which are all herebyincorporated by reference herein. The ears may also include variousgeometries and arrangements of stretch zones or elements, such asdiscussed in U.S. Pat. Publication Nos. US2005/0215972A1 andUS2005/0215973A1, which are all hereby incorporated by reference herein.

As shown in FIG. 8, the diaper 752 may include leg cuffs 796 that mayprovide improved containment of liquids and other body exudates. The legcuffs 796 may be disposed in various ways on the diaper 752. Forexample, the leg cuffs 796 may be disposed on the outer, garment-facingsurface 784 of the chassis 754; the inner, body-facing surface 782; orbetween the inner and outer facing surfaces. Leg cuffs 796 may also bereferred to as leg bands, side flaps, barrier cuffs, or elastic cuffs.U.S. Pat. No. 3,860,003, which is hereby incorporated by referenceherein, describes a disposable diaper that provides a contractible legopening having a side flap and one or more elastic members to provide anelasticized leg cuff (a gasketing cuff). U.S. Pat. Nos. 4,808,178 and4,909,803, which are both hereby incorporated by reference herein,describe disposable diapers having “stand-up” elasticized flaps (barriercuffs). U.S. Pat. Nos. 4,695,278 and 4,795,454, which are both herebyincorporated by reference herein, describe disposable diapers havingdual cuffs, including gasketing cuffs and barrier cuffs. In someembodiments, it may be desirable to treat all or a portion of the legcuffs with a lotion, as described above. In addition to leg cuffs,diaper can also include an elastic gasketing cuff with one or moreelastic strands positioned outboard of the barrier cuff. The leg cuffsmay be treated with a hydrophobic surface coating, such as described inU.S. Pat. Publication No. 20060189956A1, which is hereby incorporated byreference herein.

The diaper 752 may be provided in the form of a pant-type diaper or mayalternatively be provided with a re-closable fastening system, which mayinclude fastener elements in various locations to help secure the diaperin position on the wearer. For example, fastener elements may be locatedon the first and second ears and may be adapted to releasably connectwith one or more corresponding fastening elements located in the secondwaist region. It is to be appreciated that various types of fasteningelements may be used with the diaper. In one example, the fasteningelements include hook & loop fasteners, such as those available from 3Mor Velcro Industries. In other examples, the fastening elements includeadhesives and/or tap tabs, while others are configured as amacrofastener or hook (e.g., a MACRO or “button-like” fastener). Someexemplary fastening elements and systems are disclosed in U.S. Pat. Nos.3,848,594; 4,662,875; 4,846,815; 4,894,060; 4,946,527; 5,151,092; and5,221,274, which are all hereby incorporated by reference herein.Additional examples of fasteners and/or fastening elements are discussedin U.S. Pat. Nos. 6,251,097 and 6,432,098; and U.S. Patent PublicationNos. 2007/0078427 and 2007/0093769, which are all hereby incorporated byreference herein. Other fastening systems are described in more detailin U.S. Pat. Nos. 5,595,567; 5,624,427; 5,735,840; and 5,928,212, whichare all hereby incorporated by reference herein. The fastening systemmay also provide a means for holding the article in a disposalconfiguration as disclosed in U.S. Pat. No. 4,963,140, which is herebyincorporated by reference herein.

It is to be appreciated that the methods and systems disclosed hereinmay be utilized to monitor the quality of substrates and components aswell as respective placements during the manufacture of absorbentarticles, such as for example, topsheets, backsheets, absorbent cores,ears, waist features, and graphics printed thereon. It is also to beappreciated that the reject systems and methods described herein mayalso be utilized in combination with other types of control systems andmethods, such as described in U.S. patent application Ser. No.12/476,479, also identified by Attorney Docket No. 11347, entitled“SYSTEMS AND METHODS FOR CONTROLLING PHASING OF ADVANCING SUBSTRATES INABSORBENT ARTICLE CONVERTING LINES,” filed on Jun. 2, 2009, and U.S.patent application Ser. No. 12/476,348, also identified by AttorneyDocket No. 11348, entitled “SYSTEMS AND METHODS FOR CONTROLLINGREGISTRATION OF ADVANCING SUBSTRATES IN ABSORBENT ARTICLE CONVERTINGLINES,” filed on Jun. 2, 2009. Further, the time synchronizationfeatures of the methods and systems described herein may be utilized inother types of control systems and methods such as for example: datastorage and correlation methods with repeat application devices andmultiple application stations such as described in U.S. Pat. No.6,829,516; raw material database integration such as described in U.S.Pat. No. 7,162,319; web guide control methods and systems such asdescribed in U.S. Pat. No. 6,801,828; and data mining and trendingmethods and systems such as described in U.S. Pat. No. 6,845,278.

The dimensions and values disclosed herein are not to be understood asbeing strictly limited to the exact numerical values recited. Instead,unless otherwise specified, each such dimension is intended to mean boththe recited value and a functionally equivalent range surrounding thatvalue. For example, a dimension disclosed as “40 mm” is intended to mean“about 40 mm.”

Every document cited herein, including any cross referenced or relatedpatent or application, is hereby incorporated herein by reference in itsentirety unless expressly excluded or otherwise limited. The citation ofany document is not an admission that it is prior art with respect toany invention disclosed or claimed herein or that it alone, or in anycombination with any other reference or references, teaches, suggests ordiscloses any such invention. Further, to the extent that any meaning ordefinition of a term in this document conflicts with any meaning ordefinition of the same term in a document incorporated by reference, themeaning or definition assigned to that term in this document shallgovern.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

1. A method for rejecting defective absorbent products from a webconverting manufacturing process, the method comprising the steps of:providing a communication network; connecting a sensor with thecommunication network, the sensor including a sensor clock; connecting acontroller with the communication network, the controller including acontroller clock; synchronizing the sensor clock with the controllerclock such that the reported time of the controller clock and the sensorclock can be correlated; advancing a substrate in a machine directionthrough a converting process; virtually segmenting the substrate into aplurality of virtual segments; sequentially adding component parts tothe substrate; inspecting the substrate and component parts with thesensor; communicating inspection parameters from the sensor to thecommunication network; assigning a timestamp to each inspectionparameter, each timestamp based on the sensor clock; receiving theinspection parameters and corresponding timestamps from thecommunication network into the controller; correlating each inspectionparameter with one virtual segment based on the timestamp of theinspection parameter; identifying defects in virtual segments based onthe inspection parameters; cutting the substrate with component partsadded thereto into discrete absorbent articles; and rejecting absorbentarticles that correspond with virtual segments with identified defects.2. The method of claim 1, wherein the component parts include partsadded as a continuous web of material and parts added as a discontinuousweb of material.
 3. The method of claim 1, wherein the communicationnetwork is non-deterministic.
 4. The method of claim 1, wherein oneinspection parameter comprises a result.
 5. The method of claim 1,wherein one inspection parameter corresponds to a detected defect to thesubstrate.
 6. The method of claim 1, wherein one inspection parametercorresponds to a detected missing component on the substrate.
 7. Themethod of claim 1, wherein one inspection parameter corresponds tomeasured placement of a component on the substrate.
 8. The method ofclaim 1, wherein the absorbent articles are diapers.
 9. The method ofclaim 8, wherein the components ears.
 10. A method for rejectingdefective absorbent products from a web converting manufacturingprocess, the method comprising the steps of: providing a communicationnetwork; connecting a sensor to a remote I/O station and connecting theremote I/O station to the network, the remote I/O station including asensor clock; connecting a controller with the communication network,the controller including a controller clock; synchronizing the sensorclock with the controller clock such that the reported time of thecontroller clock and the sensor clock can be correlated; advancing asubstrate in a machine direction through a converting process; virtuallysegmenting the substrate into a plurality of virtual segments;sequentially adding component parts to the substrate; inspecting thesubstrate and component parts with the sensor; communicating inspectionparameters from the sensor to the communication network; assigning atimestamp to each inspection parameter, each timestamp based on thesensor clock; receiving the inspection parameters and correspondingtimestamps from the communication network into the controller;correlating each inspection parameter with one virtual segment based onthe timestamp of the inspection parameter; identifying defects invirtual segments based on the inspection parameters; cutting thesubstrate with component parts added thereto into discrete absorbentarticles; and rejecting absorbent articles that correspond with virtualsegments with identified defects.
 11. The method of claim 10, whereinthe component parts include parts added as a continuous web of materialand parts added as a discontinuous web of material.
 12. The method ofclaim 10, wherein the communication network is non-deterministic. 13.The method of claim 10, wherein one inspection parameter comprises aresult.
 14. The method of claim 10, wherein one inspection parametercorresponds to a detected defect to the substrate.
 15. The method ofclaim 10, wherein one inspection parameter corresponds to a detectedmissing component on the substrate.
 16. The method of claim 10, whereinone inspection parameter corresponds to measured placement of acomponent on the substrate.
 17. The method of claim 10, wherein theabsorbent articles are diapers.
 18. The method of claim 17, wherein thecomponents ears.